Facsimile transmission apparatus



April M, 1950 R. J. WISE ET AL FACSIMILE TRANSMISSION APPARATUS 12 Sheets-Sheet 1 Filed Feb. 25, 1946 I36 I34 I33 INVENTORS R.J. WISE R. D. PARROTT G.H.Rl DI NGS ATTORNE Y Aprii 11, 1950 R. J. WISE ET AL 2,503,311

FACSIMILE TRANSMISSION APPARATUS Filed Feb. 25, 1946 12 Shets-Sheet 2 3 9 mmmw INVENTO RJ. WIS R.D. PAR ROTT G.H.RIDINGS ATTORNEY April L 1950 R. .1. WISE ET AL 2,503,311

FACSIMILE TRANSMISSION APPARATUS Filed Feb. 25, 1946 12 Sheets-Sheet 3 6 a2 86 3 I3 I35 I I0! 15s '50, oo 99 92 lol INVENTORS R. J. WISE R. D. PARROTT BY G.H. RIDINGS ATTORNEY April 11, 1950 R. J. WISE ET AL 2,503,311

FACSIMILE TRANSMISSION APPARATUS Filed Feb. 25, 1946 I 12 Sheets-Sheet 4 FIG. 4

INVENTORS R. J. WISE R. 0. PARROTT BY G.H.RIDINGS ATTORNEY 12 Sheets-Sheet 5 Filed Feb. 25, 1946 FIG. 5

INVENTORS RJ. WISE a 9 m 0 w M 8 9 O. 98 3 5 O 62 l 5 55 6 7 6 0% 3 5 m a m 1 6 0 7 l u M 2 2 6 6 V ll////////////////// 5 l 7 6- m TO I 6 A/ l i s 7 fi I I iiiiiiiiii, 11 H W a w M w M W. I u 4 s7 1 TU y 7 24 7 47 6 I 3 2 7 A w 3 M/ 5 9 9 0 2 2 3 4 3 3 6 I 5 2 W 3 2 3 3 3 3 3 R.D.PARROTT G.H.R|DINGS ATTORNEY April 1, 1950 R. J. WISE ETAL 2,503,311

FACSIMILE TRANSMISSION APPARATUS Filed Feb. 25, 1946 12 Sheets- Sheet '7 FIG. 7

INVENTORS R.J. WISE R. D. PARROTT BY G.H. mamas ATTORNEY April 1950 R. J. WISE ET AL 2,503,311

FACSIMILE TRANSMISSION APPARATUS Filed Feb. 25, 1946 12 Sheets-Sheet 8 FIG. I3

I4 I 5 9o CR Ms FIG. I4

FIG. 15

|2a |2o' 9e INVENTORS R.J.WISE RDPARROTT BY G.H.RIDINGS ATTORNEY April 11, 1950 R. J. WISE ETAL FACSIMILE TRANSMISSION APPARATUS l2 Sheets-Sheet 9 Filed Feb. 25, 1946 mmN mmN

JNVENTORS RJ WISE R. D. PAR ROTT G.H. RI DI NGS ATTORNEY April 11, 1950 R. J. WISE ET AL 2,503,311

FACSIMILE TRANSMISSION APPARATUS ATTORNEY April 11, 1950 Y R. J. WISE ET AL 5 3 FACSIMILE TRANSMISSION APPARATUS 12 Sheets-Sheet 11 Filed Feb. 25, 1946 FIG I8 INVENTORS R. J. WISE R. D. PAR ROTT G. H. RlDlNGS ATTORNEY April 1950 R. J. WISE ETAL 2,503,311

FAC'SIMILE TRANSMISSION APPARATUS Filed Feb. 25, 1946 12 Sheets-Sheet I2 ATTORNEY Patented Apr. 11, 1950 FACSIMILE TRANSMISSION APPARATUS Raleigh J. Wise, Dunellen, Robert D. Barrett,

'West New York, and Gan i elti nss, Sum mit, N. .L, assig-nors .to The Western Union Telegraph Company, New York, N. Y., acorporation of New York Application February 25, 1946, Serial N o..650,074

3.3 Claims.

1 This :invention relates to facsimile telegraphy and its general object is .to provide novel tran mitting lapparatus capable of being loaded i :a plurality of messages which are scanned in .automatic sequence. Amachine of that kind presents special advantages in various commercial applications of .facsimileztransmission.

In 'a preferred form of our invention as emrbodied in a transmitter built for commercial use, .we employ a turnta'blewhich carries a series of vertical cylinders (six in :this case) for receiving copies to be scanned. .A ,single scanning device takes care of all the cylinders, which :are moved .into scanning'position oneafter theother byithe intermittent ;.operation of "the turntable. Ajfter loading the cylinders, the attendant closes :a starting switch and fromwthereon the machine .01 :erates automatically, transmitting the :messages :in sequence .toa recorder. When :the last-copy has been sent, the machine stops :itself. As .will ap- :pear later, certain operations ofgthegtransmi'tter care controlledby the recorder, whereby the two "machines cooperate for the 'automatic'transmis- .sion of a plurality .of copies.

In the actual usetofour-transmitterthere is no limit to the number of messages that can {be sent in automatic sequence. While :a :cylinder .is .being scanned, the-turntable :and the iojther cylinders stand still soi thatitheiattendantzcan remove the scanned copies :and load "the empty cylinders with fresh material. .By thus'ke'eping the cylin- .ders loaded the machine operates without interruption until :the last message has 'been :trans- 'mitted.

At the present time we prefer to use transparent ,s'scanning. cylinders: open atithetopzioninsideloadting. 'I'he'copy sheets are coiled up .and pushed down into the cylinders. This can be done quickly and requires no skill. Each'cylinder is provided :inside with novel means for;holding the inserted 'copy'firmly againstithe transparent cylinder wall throughawhich the optical-scanning takes place. A scanned copy can be lifted out of its cylinder -anda fresh copy;inser'ted in less than a minute during astationary interval of'the turntablewithout interfering with the automatic operation of the machine.

It may happen sometimes that-notall thecylinders are loaded with copy when the machine is started. To prevent waste of'time and power by the scanning of 1 empty cylinders we have an arrangement for so :a'djusting the machine that it "will stop automaticallyafteriscanni-ng I of the last :loade'd cylinder. Ihis -adjustment is :effected by simply moving an indicator to proper position. 15

2 It is further desirable that the attendant shall be ab e to d t ui h betwee can ed a d-u scann c pies an or h srurm B W p videas automatic device which marks a, scanned .copy before its removal from the cylinder.

Our multi-cylinder transmitter is a self-contained unit so compact that it can be placed on a stand or table like a typewriter orother ofilce machine. This feature of compactness is due to the novel operating mechanism in the machine and is important from, a commercial standpoint. There are many practical applications of our machine. The copies in the scanning cylinders may be standard telegram sheets or card forms used in certain business transactions, such as aeroplane reservations, or any other kinds of records containing information .to'be facsimiled to a distant .p in Our ma h n is spec a l a apted ,for

transmittinglong messages that require .a num- 'ber of cards or sheets. These are inserted into the cylinders in consecutive order and the machine does the rest.

:The various novel features that. characterize our vinvention will beexplained in a description of the accompanying drawings in which- Fig. l represents a front elevation of a transnutter embodying ourinvention;

F g-215a p anr ewof he achine;

Fig. ;3\shows the ,rightside of the machine;

Fig. 3A is a sectionon line 3A-3A of Fig. {3;

Fig. ,4 is a rear viewof the transmitter,

Fig. 5,is a vertical section on line 5-5 of Fig.2;

Fig. 6 is, a vertical section-on linen-: Qf Fig.-;3;

FigvfiA is :a-sectionon lineBA-GA of Fig. 6 showingcertain details of the scanning meche 53 1 1;

Fig.7 represents a horizontal section on ,line "1l oiFig. 1

Fig. 8 sheet;2).shows aswitch operatingdetail .on section line ,88 of Fig. '2

qFig. 9is1;a section on lin e 9-.-9 of Fig. 8; Fig. 10 (sheet 5) shows aswitch operatingde- {tail on section line -llll0 of Fig... 5, the switch abeing in closed position;

"Fig. 10A is a view similartorFig. lo with the .switchin open position;

"Figzl'l (sheet '7) shows a device for markinga scanned copy;

showing a plan view of the scanning carriage;

Fig. "14 isaside viewer-Fig. 1 3 looking from left-wright;

Fig. 15 is a section on line 15- --of Fig. 1 4

3 but turned so as to correspond in position with Fig. 13;

Fig. 16 is a diagram of the control circuits associated with the transmitter;

Fig. 17 is a diagram of the control circuits in a recorder connected with the transmitter;

Fig. 18 represents a perspective of our multicylinder machine with the outer case or cover in place;

Fig. 19 shows a one-cylinder transmitter embodying certain features of our invention;

Fig. 20 shows in plan view a scanning cylinder provided with sheet holding means operable by hand;

Fig. 21 is a vertical section on line 2l2l of Fig. 20;

Fig. 22 is a plan view of a cylinder provided with another form of manually operable sheetholding means;

Fig. 23 is a vertical section on line 23-23 of Fig. 22; and

Fig. 24 shows a turntable carrying cylinders adapted to support copies on the outside instead of inside.

The turret mechanism united parts l4|5 constitute a mounting for rotary turret mechanism TM which is one of the main features of our invention.

As best shown in Fig. 5, the turret mechanism TM comprises a casting (usually aluminum) so shaped as to provide a tubular bearing or hub I'I, an upper disk 18 and a lower disk 19. For distinction we shall refer to the upper disk l8 as a turntable and to the lower disk 19 as a driving pulley. A flanged bushing 20 is driven into the lower end of hub l1 and a ring 2| is fitted into the upper end of the hub to provide two spaced bearing points for the turret around the fixed tube l5. In this way the turret rotates easily and without vibration. If desired, a thrust washer 22 may be placed between the bushing 20 and the top of post M to reduce friction.

The turntable l8 carries a plurality of scanning cylinders 23 arranged at equal distances around the edge of the turntable. The present machine has six cylinders, but the number may obviously vary in accordance with the size and capacity of the machine. Each cylinder is mounted to rotate on the turntable independently of the others and since these mounting are alike it is only necessary to describe one of them. As shown in Fig. the turntable I8 has a circular hole 24 for each cylinder and a bushing 25 is pressed into each hole for receiving a rotary shaft 26. The

beveled upper end of this shaft carries a disk 21, preferably of bronze, which is secured by a screw 28. The disk 21 rests on the top flange of bushing 25, and a collar 29 fixed on the shaft 26 is in contact with the lower edge of the bushing, so that the shaft is held against axial displacement while being free to rotate. Each cylinder shaft 26 extends through a bushing 30 in the pulley l9 whereby the shaft has upper and lower bearings which provide a firm support for smooth operation.

The scanning cylinders 23 are mounted directly on the disks 21 and securely held thereon in any practical way. For short cylinders we prefer a screw-threaded connection as shown in Fig. 5 where the outer screw threads on disk 21 and the inner screw threads on cylinder 23 are shown in interlocking engagement at 3|. The cylinder is screwed down until it strikes the bottom flange 32 of disk 21. Thescrew threads 3! are sufficiently fine to form a rigid connection for holding the cylinder in true vertical alignment. For mounting long cylinders on the disk 21 We provide the latter with a circumferential groove instead of screw threads and fill this groove with cement. The cylinder is then forced down over the disk and held in correct position until the cement has hardened.

In the machine we are describing the cylinders 23 are transparent for optical scanning of the inserted copies through the cylinder walls. Glass cylinders have heretofore been used for this purpose but we have found certain advantages in using cylinders of plastic transparent material, such as Lucite. This material is not only optically clear but can be cut and machined to produce cylinders of accurate dimensions. For example, a long piece of Lucite or similar tubing is cut into lengths representing each a cylinder, and if screw threads are required these can be cut accurately into one end of the cylinder inside or outside.

The copies to be scanned are inserted into the cylinders 23 by simply coiling them up with the subject matter outside and pushin them down with the palm until they rest on the base disks 21. The coiled up copy, whether a thin sheet or a card, will expand against the cylinder but it is necessary to hold it in firm uniform contact with the cylinder wall during the scanning operation when the cylinder is rotated rapidly. For this purpose we have provided novel copy holding means within the cylinder. Referring to Figs. 2 and 5, each cylinder contains four pieces 33 which constitute in effect an expansible cylinder with an outer cylindrical surface 34 concentric with the inner wall of the transparent cylinder. The members 33, which may be called cylindrical sectors, are heavy pieces of metal (such as brass) arranged to move radially outward by centrifugal force during rotation of the cylinder. Each sector has a pin 35 in the bottom projecting loosely into a hole 36 in disk 31, on which the sectors are supported for individual movement.

The weighted sectors 33 normally provide a narrow annular space 31 (Fig. 5) for receiving the inserted copy 38. The top edges of the sectors are beveled to facilitate the insertion of copy. When the loaded cylinder is rotated, as will be described later on, the sectors 33 automatically move outward and press the copy firmly against the adjacent wall of the cylinder. Since these sectors present a substantially unbroken cylindrical surface 34 against the paper. the latter is held with uniform pressure over its entire area against the rotatin cylinder. The pins 35 have suflicient play in the holes 36 to allow the necessary movement of the centrifugal sectors. A scanned copy is easily removed by grasping it at the top where it extends above the sectors 33, as will be clear from Fig. 5. The sectors are simply dropped into the cylinder through the open top and require no further attention once they are in place.

The turret TMisrotated intermittentlyto Bring the cylinders 23' into scanning position one after the other. In the present machine where there are six cylinders the turret is rotated thr'o'ugh an arc of 60 to move the next cylinder into line for scanning. This op-eration of the turret isdone by a small electric motor 39 mounted on a block 40 which may be cast integral with base It. A vertical shaft 41' is connected to the motor shaft through a worm drive (not shown) and the upper end of shaft 4| carries a disk 42 whichhasa hub iiortion 43 and a pin 44. The parts 42-43 may be cast in one piece and this casting is cured to shaft 4! by 'a set screw 45' or other" s'e'. A grooveddi'sk'or' small pulley 4G is loosely mount: ed on the hub 43 or disk sz'e'nd carries a vertica pin 41 arranged to be engaged by a stiff leaf spring. 48 which is attached at the center to pm 44. As shown inFigs. 2 and 7, the spring pa ses through a slot in pin 44' and is secured in place by a screw 49.

A driving belt" 50' connects the grooved pulleys l9 and 46, which are in horizontal alignment as shown in Fig. 1. The motor 39 turns the sprin arm 48 clockwise" (as viewed in Fig. 2) and this arm engages the pin 4! to drive the turret pulley 46 in the same direction. As will be explained later, the turret is automaticall locked in each operated position; and this means that the turret comes to an instantaneous stop. It is the function of spring 48to' act as a resilient driving connection between the motor 39 and the pulley 46 so as to relieve the motorof shock at the sudden stopping of the turret.

We shall now describe the mechanism forrotilting the particular cylinder that is in scanning position. To distinguish this' cylinder from" the others we have marked it 23a in the drawings (Figs. 2 to 5). As previously explained, the vertical' cylinder shafts 26 extend through and'b'elow the pulley I9. A driving" shaft 5| projects upward from the base I ll in axial alignment with'the' shaft 25 of cylinder 23a but separated therefrom, as best shown in Fig; 5. The shaft 5| is mounted on a U-shaped bracket 52 which is secured to the base H) by screws 53. A motor 54' mounted on the machined surface we of base H! has a worm 55 in mesh with a worm gear 56' on shaft5| whereby the latter is rotated at reduced speed.

On the upper portion of the cylinder driving shaft 5| is mounted an adjustable clutch unit K which comprises a sleeve 5'l, a friction disk 58 and a washer 59. The sleeve 51 is slidable on shaft 5| but is locked thereto for rotation by a set screw 60 in the sleeve engaging a key way 6| in the shaft. A washer 62 hired to the top of the shaft 5| provides an annular stop for the upper movement of clutch sleeve 57, which normally rests on top of bracket 52 (Fig. 5). The friction disk 58 is loosely mounted on sleeve 51 so as to rotate thereon when necessary. The washer 59 is screwed to the upper end of sleeve 51' and cooperates with disk 53 to form a friction clutch under the pressure of a coil spring E33 which is seated in a groove formed by a flange 64 on sleeve 51 and the conical hub 85 of disk 58. As the spring tends to contract, it pushes the disk 58 up against the washer 59 whereby these two parts constitute a frictional drive between the shaft 5| and the disk 58. A vertical pin 56 on disk 58' is arranged to engage a horizontal pin 6'] on the lower end of each cylinder shaft 26 whenthe clutch unit K is in raised position.

The clutch unit is operated by lever'ts which is iv'ote'd' in anotch" on top of bracket 9 standing up from base In. This lever hasa forked end in engaging a groove-'11 in sleeve 5.1, as shown in Figs. 5 and 6. The bracket 69 supports an electromagnet 12 which has a laminated plunger 12" for actuating the clutch lever 68. A convenient way to connect the plunger with the lever is to mount a pin 73 between a pair of projecting end plates 13' 'of the plunger. When the solenoid is energized, the plunger is pulled down and the cross pin 13" rocks the lever 68 to raise the rotating clutch K into operative position, whereby the pin B6 connects with the pin 6? on the aligned cylinder shaft 25. The cylin der' 23a is now rotated at scanning speed (say 300 R. P M.) until the inserted copy has been completely scanned and transmitted to the associated recorder.

When the solenoid 12 is deener'gi'zed, the heavy clutch drops by gravity to normal position where the driving pin 65 is out of the way of the connecting pins G! on the cylinder shafts 26 so as not to interfere with the operation of the turret. The timing of solenoid 12 will be explained in connection with Fig. 16. To insure the instant stopping of cylinder 2301. when the driving con nection lit-61 is broken, we provide a brake 14 for each cylinder shaft 26. These brakes may be leather or rubber pads carried by spring arms I4 which are riveted to angle brackets 75. These brackets are fastened to the underside of turntable It by screws 15". See Figs. 1, 2, 3, 4, and '7. The brakes 14 also act as a load on the cylinder shafts 2c and prevent chattering thereof.

The scanning mechanism A single scanning device does for all the cylinders, which are brought into scanning position one at a time. Viewing the machine from the front, the cylinderin scanning position is the one at the rear marked 23a (Fig. 2). Theoptical parts of" the scanning mechanism are mounted on a vertically movable carriageCR of novel construction, as best shown in Figs. 13 to 1.5. A U-shaped plate 76 of sheet metal has rearwardly extending sides Hand; 18. A tube is is soldered or otherwise attached to the front of plate It and this tube is slidably mounted on a stationary ost or red 88 which extends between the base Hiand a topplate 3| to which the rod is fastened by a screw 82. To reduce friction and produce a smooth easy movement of tube 79 on rod 8|), the tube is furnished with an upperbushing 83 and a lower bushing 84 (preferably bronze) which act as bearings for the tube, as shown in Fig. 6.

The carriage GR, is prevented from turning on rod fill by connecting it to a guide rod or post 85 fixed between the base I!) and the top plate 8| to which the rod is secured by a screw 86. A bracket 31 fastened to'the side is or plate is by screws 8'! extends around the rod 85, and a screw 88 connects the outer end of the bracket to'the plate. It isclear' from Figs. 4 and 13 that the spring arm 87a of bracket 81 is adjustable to correct position with respect toth guide rod 85 by simply turning thescrewtss'o as to obtain a close sliding fit between the carriage and the guide rod. This prevents twisting or turning of the carriage without interfering with its vertical sliding movements.

The u-shaped plate it carries the optical parts of the scanning mechanism comprisingan exciter lamp 29', a projection tube 90; a pickup tube 5H, and a photocell 92. It' will not b'e'n'ecessa'r'y to describe tnese parts detail because their construction is well known. We need only say that the light from lamp 89 passes through the lenses of the tube 90 to form a scanning spot on the copy in cylinder 23a. and from there the light is reflected through the lens assembly in pickup tube ill to the sensitive cathode of photocell 92. The path of the light beam is indicated by the dashdot lines 93-94 in Fig. 3. v

The exciter lamp 89 is mounted on a suitable base 95 arranged at the proper angle and secured to a U-shaped bracket 96 extending from the side wall 1! of the U plate '16. The bracket 96 is fixed to the plate I? by screws 96' (Fig. 15). The projection tube 90 is attached to the side wall H by a slotted plate 9' (Fig. 3) which is clamped in adjusted position by a pair of screws 98 passing through slots 91 in the plate. This adjustment of tube 90 is in an axial direction to focus the light on the copy to be scanned. The pickup tube 9| is similarly mounted on the side wall TI in adjustable position by means of a slotted plate 99 and one or two screws I00. The photocell 92 is mounted on a suitable base IOI which is attached to the left side 18 of U plate I6 by screws IOI. The base IOI has a tubular extension I02 for mounting the photocell. A lightproof cap or cover I03 slipped over the extension I02 completely encloses the photocell except for a slit I04 to admit the scanning beam.

A small electric motor I05 is mounted in the rectangular chamber of U plate '16 and is secured by studs I06 to the front wall of the plate, as shown in Fig. 13. The rear end of motor shaft I'I carries a slotted disk I08 for interrupting or chopping the light beam as it passes from the pickup tube 9| to the photocell 02. The disk I08 turns at a definite speed to produce a carrier current of prescribed frequency, as will be understood without further explanation.

The slow downward movement of scanning carriage CE is effected by a vertical screw shaft I09 which is journaled in the base plate I0 and the top plate 8 I. As shown in Fig. 5, the lower end of shaft I09 extends into the base chamber I3 and carries a gear I In which is in mesh with a pinion I I2 fixed on the lower end of drive shaft The screw shaft I09 is thus driven continuously at the proper speed. The carriage GR is normally disconnected from the screw shaft I09 and is connected thereto by a device which we shall now describe.

A sleeve I I3 is rotatively mounted on the tube 19 of carriage CR and is held against sliding movement by the lower edge H4 of U plate I6 (Fig. 3) and by a collar I I5 secured to the tube by screws I I5. The sleeve I I3 carries a channel bar or bracket H0 (Figs. 3 and 14) which may be soldered in place, and a half nut H1 is pivotally mounted between the flanges of the bracket by means of a pin H8, as shown in Fig. 6A. When the bracket H6 is rocked counterclockwise, the half nut I I1 engages the screw shaft I09 whereby the carriage CR is connected for downward scanning movement.

The half-nut bracket I I9 is operated by an electromagnet or solenoid I I9 which is secured to the bottom of the U plate I6 by a cross plate I20 soldered to the bottom edges of side walls I1 and I8. Four screws I20 connect the solenoid to plate I20. A channel arm I2I is suitably attached to the sleeve H3, as by soldering, this arm being above the bracket H6 and extending at right angles thereto. The plunger I22 of electromagnet I I9 has a pair of extensions I23 which carry a horizontal pin I24 arranged to engage a vertical pin I25 on the outer end of channel arm I2I. When the solenoid H9 is energized, the plunger I22 is pulled in and the pin I24 rocks the bracket H0 to connect the half nut I I! with the rotating screw shaft I09. The pivotal mounting of the half nut on pin I I8 allows it to adjust itself fully to the screw threads on the shaft.

When the solenoid H9 is deenergized, a contracting coil spring I26 pulls the parts back to normal position, as shown in Fig. 6A. A pin I2'I (Fig. 3) depending from a corner of the bottom plate. I20 is in the path of channel arm I2I and forms a stop to limit the return movement of the parts. One end of spring I26 is attached to the pin I25 and the other end is fastened to a screw I26 on an angle bar I28 which projects laterally from the bottom of U plate I6. The angle bar I28 is secured by screws I29 to a cross strip I30 which is soldered to the sides IL-l8 over the cross plate I20, as shown in Fig. 15.

We have explained how the scanning carriage CE is moved down by the screw shaft I09 during the scanning operation. Now we shall describe how the carriage is automatically returned to normal position when the half nut I I1 is released from the screw shaft. The top plate 81 is firmly supported on an iron pipe or post I3I which is screwed to the base plate I0 and locked by a nut I32. As shown in Fig. 7, the post I3I is at the left rear corner of the base and the plate 8| is secured to the top of the post by screws I33 (Fig. 2). A pair of depending brackets I34 and I35 are fastened to the opposite ends of plate 8| by screws I30 and I3? respectively.

The left bracket I34 carries a stud I38 on which a rotary spring drum I39 is mounted and a second spring drum I40 is mounted on a stud I4I carried by the other bracket I35. The engineers refer to these spring drums as recoils. There is no need to show or describe the structural details of the spring drums because they are well known return devices used on various machines. However, while such spring drums are old in themselves, we have incorporated these elements in a novel combination to produce a scanning mechanism of new construction. In the particular design of the machine illustrated, the spring drum I39 is positioned in front of bracket I34 and the other drum is arranged behind the bracket I35, so that the recoils are not in transverse alignment with respect to the scanning carriage CR, as best seen in Fig. 2.

The left recoil I39 carries a small pulley I42 which rotates with the recoil on shaft I38 to which one end of the fiat spiral spring inside the recoil is connected. A tape or narrow belt I43 is wound on the pulley I42 and connected thereto at its inner end, while the outer end I44 of the tape is connected to an arm I45 secured by a screw I46 to a corner of the U plate I6 (Fig. 6). The outer end I44 of tape I43 may be in the form of a metal loop fastened to the arm I45 by a screw I4'I. A similar tape I48 is connected to and wound over the drum I 40, and a metal loop I49 at the outer end of the tape is connected by the screw I26 to the angle bar I 28 (Figs. 3 and 6). The lower portion of loop I49 passes through a slot I28 in the angle bar, as shown in Fig. 13.

It is clear then that the recoils I39 and I40 are connected to opposite sides of the scanning carriage CR at the points I47 and I21, respectively. As the carriage moves down when the half nut H'I engages the screw shaft I09, the fiat spiral springs in the drums I39 and I40 are wound up 2,sos,s1 1

until the carriage reaches the end of its downward travel. The moment that the carriage is released from the screw shaft I169 by the deepergizing of magnet .I IS, the tension springs in the recoils pull thecarriage instantly back to normal position. There is a rubber cushion I50 at the top of rod 86 to form a silent stop for the return of the carriage which is firmly held in its normal raised position by the spring drums.

In the machine shown in the drawings the shaft I58 of drum I39 is nearer to the center of gravity of the scanning carriage CR than is the shaft I ll of drum I 40. Therefore, to equalize the upward pull of the recoils the tape I43 of drum I39 is wound on the pulley I42 of reduced diameter in order to increase the torque of the spring. In other words, if we regard each drum as acting through an imaginary lever arm extending from the center of the drum to a vertical line passing through the center of gravity of carriage B,,it will be seen that the drum I39 acts through a shorter arm and therefore must have more lifting power than the drum I46. As the carriage moves down, the spring in drum I39 is wound up ata faster rate than the spring in drum I46 whereby the lifting power of the two vrecoils is equalized and the carriage moves smoothly up and down.

The operation of the optical scanning mechanism will be understood without further description. It is only necessary to say that as the cylinder 23a rotates rapidly, the light spot focused on the copy moves slowly downward and the light variations thus produced cause the photocell 62 to generate a carrier frequency which is modulated in accordance with tone values of the transmitted copy. We usually operate the scanning cylinder at 300 R. P. M. and the scanning speed of the carriage is such that the copy is scanned at 100 lines per inch for the best results.

We utilize the copy-holding members 53 to generate a phasing signal for the recorder. The tops of these members are painted black to form a circular black band II as shown in Figs. 1 and 5. The inserted copy 38 leaves a gap I52 lengthwise of the cylinder andthis gap exposes a rectangular portion I5I of the blank band I5I to the scanning beam, no matter where the gap occurs. The rest of the cylindrical sectors 33 is white like the copy and scans like a blank surface. Placing the mark I5! on the inner cylinder 3t.- obviates the necessity of printing it on the copy itself, as done h retofore, so that no specially prepared copy is required. Since the operation of phasing marks in facsimile systerns is well known, we need not show or describe any circuits controlled by the phasing band I5I Switch controls in the transmitter The transmitter contains a number of switches for controlling various electrical parts and we shall now describe how the switches are operated. The top of the tubular extension I! of turret TM carries a plug I53 which is fixed in place by a set screw I54. A rotary cap I55 is fitted on plug I53 (Figs. 5 and 8) and is formed with an integral radial projection I55 which acts as a pointer or indicator. The cap I55 is fastened. to the top of rod I55 by a set screw I5! or otherwise. The rod I56 passes with a tight fit through a hcle in plug I56 and the lower end of the rod turns snugly in a bushing I58 at the bottom of the hollow post It. A cam disk 556' is fixed on the lower end of rod I56 in rubbing contact with the bushing I58 which cooperates with the plug I53 to hold the 16 rod against axial displacement. The disk I is cut away at the .periphery to provide a straight edge I59.

The cap I 55 carries a spring-pressed pin I66 arranged to engage notches MI in the top edge of plug I53. As shown in Fig. 8, the notches I6! have a slanting cam surface I62 and a vertical locking shoulder I63. Consequently the cap I55, which acts as a finger piece, can be turned leftwise by hand, for the pin I66 rides over the cam surfaces I62. There are as many notches I6I as there are cylinders on the turntable I6 and these notches are arranged in radial alignment with the cylinders. Whenever the pin I snaps into a notch I6I, the indicator I55 points to one of the cylinders 23, as shown in Fig. 2. In other words the finger piece I 55 can be turned counterclockwise to select any particular cylinder for a purpose to be presently explained. When the turntable I8 is rotated clockwise by the motor -36, as previously described, the cap I55 and rod I56 turn with it due to the frictional contact of those parts with the plug I53.

The cam disk I59, which turns with the rod I56, operates a switch I64 of any practical type, such as a microswitch of well known construction which need not be described. This switch has an operating arm I65 extending outside the casing. The free end of this arm is in pressure contact with the edge of disk I59. As long as the arm I65 engages the circular edge of the disk (Fig. 10) the switch I 64 remains closed, but when the arm I65 engages the straight edge I59 of the cam disk (Fig. 10A) this arm moves outward and opens the switch. At this point we need only say that when the switch I64 is closed the transmitter is connected to its source or power and the opening of the switch cuts ofi the electric power from the machine, which thereupon stops. How that is done will be fully explained in connection with the circuits of Fig. 16.

The switch I64 may therefore be regarded as the start and stop switch of the transmitter and is controlled by the hand knob I55 which not only starts the machine but determines when the machine shall stop. .To understand this fully, let us look at Figs. 2, 10 and 10A. For the sake of explanation we shall assume that the attendant has only three messages to transmit, which he leads into the first three cylinders marked No. 1, 2 and 3-. He turns the switch knob I55 until the pointer I55 indicates cylinder No. 3. the last one that is to be scanned. The disk I59 is now in the position shown in Fig. 10 where cylinder No. l is in scanning position and the switch I64 is closed. The machine is now running to scan and transmit the copy in the first cylinder.

Aiter the scanning of cylinder No. 1, cylinders No. 2 and No. 3 are successively brought into scanning position by the timed operation of turntable I8. After cylinder No. 3 has been scanned, the switch I64 is still closed and. the first empty cylinder Nol is moved into scanning position. When that happens the disk I59 is in such angular position that the switch arm I65 engages the straight edge I59 of the disk and the switch I64 snaps open. The machine, therefore-stops automatically after scanning of the last loaded cylinderas determined by the position of the indicator knob I 55.

If all six cylinders are loaded, the attendant moves the pointer I55 to cylinder No. 6 so that all the cylinders will be scanned in automatic sequence. The cylinders can be kept loaded by replacing scanned copies with fresh ones and adjusting the switch knob I-55 to indicate the last loaded cylinder. In this way the machine can be kept going to transmit an indefinite number of copies without interruption. To stop the machine at any time it is only necessary to turn the knob I55 until the switch I64 is opened by the cam disk I59.

" Referring to Fig. '1, the turret mechanism is locked in scanning position for each cylinder by a dog or latch I66 mounted on a pivot I61 which is a vertical stud projecting from a post I68 secured to base I by screws I69. The latch I66 has a notch I shaped to receive the cylinder shafts 26. The location of notch I10 is such that when a cylinder is in scanning position the notch engages one of the shafts 26 and locks the turret TM against rotary movement. A contracting coil spring I1I attached to the rear end of latch I66 and to the post I68 holds the latch locked to the engaged shaft 26.

The latch I66 is operated to releasing position by a solenoid I12 which has a plunger I13 connected to the latch by a pin I14. When the solenoid is energized, as will be explained in Fig. 16, the plunger I13 is pulled in and the latch I66 is rocked away from the turret, thereby withdrawing the notch I10 from the shaft 26. The turret is now rotated to bring the next cylinder into scanning position. The solenoid I12 is deenergized after the shaft 26 has moved clear of the notch I10. As the turret continues to turn, the next shaft 26 rides over the curved edge I15 of the latch until it encounters the notch I10, whereupon the turret is locked for the next scanning operation.

The upright post or stand I68 carries a bracket I 16 secured by screws I11 which pass through horizontal slots I18 in the bracket to permit lateral adjustment thereof. The bracket I16 has an arm I19 (Figs. 2 and 3) which carries a pair of switches I80 and I8I secured to opposite sides of the arm by screws I82. These two switches, like the switch I64, may be of the so-called microswitch type which are so well known as to require no description. It is enough to say that the upper switch I80 has an operating arm I83 and. the lower switch I8I has a similar arm I84. The switch I80 is normally open and is closed when the arm I83 is moved toward the switch box. The switch I8I is normally closed and is opened by the arm I84 being moved toward the switch box.

The switch arm I83 has a roller I83 arranged to be engaged by a lever I85 pivoted on the stud I 61 above the latch I66. The lever I85 is normally urged toward the turret by a coil spring I88 connected to the rear of the lever and to the post I68, as shown in Fig. '1. The rear edge of lever I85 has a recess I81 and a curved end portion I88. When the turret is locked in any one of its scanning positions. one of the cylinder shafts 26 rests in the recess I81 and the associated switch I83 is not engaged by the lever I85. However. when the turret is turned clockwise, the shaft 28 moves out of recess I81 and rides over the curved surface I 88, thereby actuating the switch arm I83 to closing position. In other words, the switch I80 is held closed as long as the shaft 26 engages the curved edge I88 of lever I 85. The function of switch I80 will be explained in connection with Fig. 16.

The switch arm I84 has a roller I84 at its free end arranged to be engaged by the latch I66 when the latter is operated by the electromagnet I12 to release the turntable, as previously explained.

As long as the notch I10 of latch I66 engages a cylinder shaft 26, the switch arm I84 is clear of the latch and the switch I8I remains in normal closed position. However, when the latch I66 is moved outward into releasing position by the solenoid I12, the latch operates the arm I84 to open the switch I8I. This switch remains open as long as the shaft 26 rides over the curved edge I15 of latch I66. The moment that the moving shaft 28 encounters the notch I10, the spring I1I rocks the latch rearward (that is, toward the turret) and the switch I8I is again closed. The purpose of this switch will be explained in the description of Fig. 16.

A normally open microswitch I89 is mounted on the pipe I3I' (Fig. 6) by means of a band I90. This switch has an operating arm I9I arranged in the path of the scanning carriage CR. In the present design of the transmitter, the bottom I92 of solenoid II 9 strikes the arm I9I to close the switch when the carriage is at the end of its downward movement. The closing of switch I89 automatically disconnects the half nut I I1 from the screw shaft I09 so that the carriage OR is free to be returned to normal position by the spring drums I39 and I40. The circuit connections controlled by switch I89 will be described in Fig. 16.

The switch I89 also controls a marking device MK (Figs. 11 and 12) for automatically marking a scanned copy before its removal from the cylinder. This marker comprises an arm I93 pivoted on a stud I94 which is carried by a bracket I95. This bracket is fastened to the top plate 8! by screws I98. The free end of arm I93 carries a suitable marking point I91. A coil spring I98 on stud I94 normally holds the arm I93 in raised position, as shown in Fig. 11. The solenoid I99 attached to the underside of plate 8I has a plunger 200 connected by a thread or thin wire 20I to a small pulley 202 rotatable on the stud I94. The pulley 202 is attached to the arm I93 in any practical way and. acts as a bearing for the arm. When the solenoid I99 is energized and pulls its plunger in, the pulley 202 is rotated to swing the arm I93 into marking position, as indicated by the dotted lines I93. The point I91 places a suitable mark on th scanned copy 38 in cylinder 23a before the turntable is moved to the next scanning position.

Control circuits of transmitter and. recorder (Figs. 16 and 17) The source of power for the transmitter is represented in Fig. 16 by a pair of bus bars A and B. An auxiliary bus bar A is connected to bus bar A through a switch 203 operated by a relay 204. The switch 203 is normally open and is closed only when the relay is energized. To simplify the circuits in Fig. 16 we have indicated the connection of a terminal or conductor with the bus bars A, B and A by using arrows marked with those letters. It will be understood that any device connected to conductors A and B is not included in the power circuit unless the relay switch 203 is closed. In describing the circuits we use the term wire to indicate any kind of electrical connection.

One side of relay 204 goes to the power main B and the other side is connected by a wire 205 to the arm I of switch I64. In the mechanical structure of switch I64, the arm I65 is an operating member for the contact parts inside the switch box, but for convenience we have used the arm I65 in Fig. 16 as a movable contact adapted to engage a fixed contact I65 which is connected 1 3 to bus. bar A.. Therefore, when the attendant turns the knob- I55 to close the switch I64, relay 204. is energized to connect the auxiliary bus bar A to bus bar A.

The closing of relay switch 203, closes the circuit of. scanning motor 54 which. is. connected by lines 298. and- Zfil to bus; bars A. andiB. The exciter lamp 89 and chopper motor Hi5- are. con.- nected across the lines. 206I.. Therefore, when. the startingsw-itch M54 is closed, the optical scanning. mechanism is energized, but the: carriage OR is not yet moving. At the same time, since the switch. I8I. is closed, the clutch. magnet "I2 is; energized to. raise the clutch K into connecting position whereby the motor 54 rotates the particular cylinder that happens to be in position for scanning. It will be clear that the motors 54'. and I05 and the exciter lamp 89 are energized continuously as long as the relay switch 203. is closed.

To simplify the switch connections for clutch magnet 12 we have assumed the arm HM to be a movable contact: member normally closed against a fixed contact IBM which is connectedto oneside of the magnet. The other terminal of this magnet goes to bus bar B and the movabl contact I84 is connected tobus bar A so that the clutch magnet l2 remains energized as long as the switch contacts I84-I84a are closed. This occurs during the scanning of each cylinder while the turret is locked by the latch. I66. When the magnet '12 is deenergized at the end of a scanning operation (as will presently be explained) the clutch K instantly drops to releasing position to permit operation of the turret.

The motor 39, which operates the turret (represented in Fig. 16 by the turntable l8) has one terminal connected to bus bar B and the other terminal to a wire 268 which goes to the fixed contact I 83 of switch I80. The arm I83, previously described as an operating member outside the switch box, is used here as a movable contact connected to bus bar A and operated by the lever I85 to close the switch I80 for energizing the turret motor 39. The driving belt 5!} is shown connected to the turntable I8 to simplify the drawing.

To understand the operation of the other circuits and control devices in the transmitter, it is necessary to see what happens at the recorder during the scanning operation. The. modulated carrier or signal frequency generated by the photocell 92. passes through an amplifier 289 which is connected by a pair of transmission lines LI. and L2 with a recorder illustrated diagram.- matically in Fig. 17. The amplifier 2M is connected to the power lines A and B when the relay 204 is energized upon operation of the starting switch I64. We might say here that Fig. 1'?

is in certain respects a simplified form of Fig. 14 of Ridings and Wise Patent. No. 2,385,263, issued October 9, 1945', except that this patentv contains no provisions for controlling a multi-cylinder transmitter.

The modulated signal frequency or carrie tone received by the recorder of Fig. 17 passes through a signal inverter 2H0, then through an amplifier 21 I, the output of which is connected to a transformer 2I2. The secondary coil 253 of this transformer is in the circuit of a stylu 244 which acts on electrical recording paper mounted on the scanning cylinder "2I5. This. arrangement is well known in the facsimile art and requires no further description. It will be understood that the electric impulses in the recorder circuit cause the: stylus ltd to mark the recording paper so as to produce an exact duplicate or facsimile of the transmitted copy. 1

An amplifier 2I6 at the recorder is connected to lines LI and L2 and the amplified output of this amplifier energizes a line relay 2I'I to close a switch 218 and thereby energize a slow-acting relay 2I9. This relay remains energized as long as signal current flows through relay 2! 'i, that is, during the scanning of copy at the transmitter. The vibratory movements of switch 2E8 due to the alternating current. that flows through relay 2II have no eirect on relay 2I9 which remains energized during the brief open intervals. of switch 2I8. For convenience we have shown a simple battery circuit 220 for relay H9.

The energization of relay zit closes the associated make. contacts 22! and 222. The fixed member of the pair of contacts 22I is connected by a, wire 223 tothe bus bar D and the movable member is connected by a wire 22% to one terminal of a motor 225 which operates the recording cylinder 2I5. The other. terminal of motor 2-25 is connected to bus bar C. It will. be understood. that the bus bars CD represent any suitable source of electric power for the recorder. The other switch 222 controlled by the relay 2I-9 has its fixed contact connected by a wire 225 to transmission line L! and. its movable contact is connected by a wire 22'! to the fixed contact of a normally closed switch 228. The movable contact of this switch is connected to. a suitable source of positive direct current potential in dicatedby the arrow 229 We have now described enough of Fig. 17; to understand. what happens at the. recorder when the starting switch I64 at the transmitter is closed by the operation of knob I55. Assuming a loaded cylinder to be in scanning position, the preliminary scanning of the black phasing mark I541 in the transmitting. cylinder sends a carrier signal over the lines LI, L2 to the recorder where the energized relay ZI'l closes the switches 22! and 2.22 to energize the scanning motor 225 and put a. positive potential on. line Li. This positive potential operates. a polarized relay 235] at the transmitter to move the armature 23! against the M contact.

The winding of relay 235 is connected to line LI by a. wire 23 2 which contains a choke coil 233 to prevent the passage of carrier frequency through the relay. A pair of blocking condensers 234 and 235 in lines LI and L2 at the output end of amplifier 2519. prevent any direct current potential bias impressed on the transmission lines from interfering with the. carrier frequency. The choke coil 233 preferably has a grounded con.- denser 233' connected in series to act as a bypass for shunting any inductive surge produced by a reversal of potential on line L! away from the winding of relay 236.

Still referring 00' Fig. 1.6-, the armature of polarized relay 23.0 is connected to the auxiliary bus bar A and the contact M is connected by a. wire. 2-36. to one side of a. relay 23?, the other side of which goes. to bus bar B. Therefore, when the M contact. of relay 2% is closed, the relay 231 is energized and closes its contacts 238-239 which are normally open. The movable contact 238 is connected to bus bar A and the other contact- 239 is connected to one side of the solenoid H9 which operates the half nut Ill. The

other side of solenoid I 59 goes to bus bar B. It

will thus be seen that the positive potential put .on line LI at the recorder automatically'connects the scanning carriage CR of the transmitter to the feed screw I69. The transmitter is now in full operation and the recorder makes a record of the transmitted copy.

The relay 231 also operates a pair of break contacts 246-24I and a pair of make contacts 246-24I'. When the relay 231 is energized by the positive potential on line LI, the switch contacts 249-24I are closed to put a positive potential on line L2 from a rectifier 242. This is done through the following connections:

The rectifier 242 is connected to the power mains A and B so that it is energized when the starting switch I64 is closed. The output lines 243 and 244 of the rectifier are controlled by a relay 245 which has a pair of make contacts 246-241, break contacts 246-246, make contacts 248-248, and break contacts 248-249. The contacts 246 and 248 are connected to the positive lead 243 of the rectifier. The contacts 241 and 249 are connected to the negative lead 244 of the rectifier through a resistor 256. The movable contact member 248 is grounded and the other contact member 246 is connected by a wire 25I to the contact 24I of relay 231. When this relay is energized, positive potential goes from line 243 through closed contacts 246'-246, wire 25I, closed contacts 24I-246, wire 252, closed relay switch 253, wire 254, and through choke coil 255 to the line L2. The choke coil 255 may have a grounded condenser 255' connected in series for the same purpose as condenser 233 for choke coil 233 on line LI.

The positive potential impressed at the transmitter on line L2 aflects the recorder in this way: A polarized relay 256 is connected to line L2 and its armature 251 is connected to the bus bar C. When this relay is energized by the positive potential on line L2, the armature 251 closes the contact M which is connected by a wire 258 to one side of a blank feeding and mounting mechanism represented by the labeled rectangle BF. The other side of this mechanism is connected by a wire 259 to the bus bar D. For

the details of mechanism BF, which is not part of our present invention, see the Ridings and Wise Patent No. 2,386,263 previously mentioned. It will be understood then that the positive potential impressed on line L2 at the transmitter energizes the mechanism BF at the recorder to feed a blank to the recording cylinder 2I5 and mount it thereon in position to be engaged by the recording stylus 2 I4.

Still referring to Fig. 17, it should be noted here that the closing of contact M by the armature 251 also closes the circuit of a relay 266 which has One side connected to contact M by wires 258 and 26I. The other side of relay 266 is connected by a wire 262 to bus bar D. When the relay 266 is energized, it breaks its contacts 263-264 and thereby prevents the energizing of the blank stripping mechanism ST, the details of which are set forth in the aforementioned Patent No. 2,386,263. One terminal of mechanism ST is connected by a wire 265 to bus bar C and the other terminal goes to bus bar D through a control device 266, wire 261, relay switch 263-264 and wire 268. The rectangle 266 represents an arrangement for preventing operation of the stripping mechanism before the relay 266 is energized to open the switch 263-264. Such an arrangement is fully disclosed in Fig. 14 of Patent No. 2,386,263 and requires no description here sinceit is not a part of our invention.

We now have the transmitter and the recorder ward movement and closes the switch in operative condition so that the scanned copy in the transmitter is recorded by the stylus 2I4 in the recorder. The positive potential remains on line L2 during the scanning operation until the carriage CR reaches the end of its down- I89. Thereupon the following operations take place automatically At the transmitter a relay 269 is energized through a circuit including a wire 216 which connects one side of the relay with bus bar A through the closed switch I89, the other side of the relay being connected to the power main B. The energized relay breaks its contact 253 and thereby removes the positive potential from line L2. The closing of relay contacts 21I-212 closes the direct current circuit of relay 213 which closes its contacts 214 to energize the solenoid I99 and operate the marking device MK.

At the recorder the removal of positive potential from line L2 breaks the contact M which releases the relay 260 to close the contacts 263-264, whereby the mechanism ST is energized to strip the recorded blank from cylinder 2I5. At the completion of the stripping operation a relay 215 is energized to open the switch 228 and close the switch 216, whereby the positive potential on line LI is replaced with a negative potential from a suitable source 211. In Fig. 17, the relay 215 is shown connected to the stripping mechanism ST through a normally closed switch 218 of a relay 219 which is not energized now. For full details of how the relay 215 is automatically energized at the completion of the stripping cycle, see the aforesaid Patent No. 2,386,263.

At the transmitter the negative potential on line LI causes the armature 23I of polar relay 236 to close the contact S which is connected to one side of a relay 286 by a wire 28I. The other side of this relay goes to the bus bar B. Therefore the closing of contact S by armature 23I energizes the relay 286, which closes three pairs of contacts 282-283, 284-285 and 286-281. The two movable contacts 282 and 284 are connected to bus bar A and the other movable contact 286 is connected by a wire 288 to contact 24I of relay 231. Contact 283 is connected by a wire 289 to relay 245, and contact 285 is connected by a wire 296 to one terminal of the turret motor I39. Contact 281 of relay 286 is connected to wire 25 I.

Still at the transmitter, the negative potential on line LI causes the polarized armature 23I to break the M contact, whereby the relay 231 is deenergized and the open switch 238-239 breaks the circuit of solenoid II9. Consequently, the half-nut H1 is withdrawn from the screw shaft I69 and the scanning carriage CR is instantly pulled up by the spring drums I39 and I46. The initial upward movement of the carriage opens the switch I89 so that the relay 269 is deenergized with the instant release of relay 213 and the marking solenoid I99. The circuit of relay 213 may include a condenser 29I shunted by a resistor 292 to accelerate the deenergizing of the relay, whereby the marking solenoid I99 receives a mo mentary impulse to mark the scanned copy.

' The closing of its three switches by the energized relay 286 results in the following operations which take place automatically in the transmitter upon completion of the stripping cycle in the recorder:

1. The closing of switch 282-283 energizes the solenoid I12 through a wire 293 to withdraw the 

